Todd Armstrong Leads Project on Anti-Social Behavior

Todd Armstrong is currently working with CJ graduate students Shawn Keller and Scott Macmillan on a project relating autonomic nervous system function to variation in antisocial behavior. This project builds on research findings that measures of autonomic nervous system arousal are consistently related to measures of antisocial behavior, including crime and delinquency. Among this work, an individual's resting heart rate often serves as a measure of autonomic nervous system arousal. Based on a meta analysis of the literature testing the relationship between heart rate level and antisocial behavior, Ortiz and Raine (2004) concluded that "low resting heart rate appears to be the best-replicated biological correlate to date of antisocial and aggressive behavior in children and adolescents" (p. 154).

While the relationship between low resting heart rate and aggressive and antisocial behavior is well established in the literature, studies to date have not yet identified the characteristics that mediate this relationship. Raine (2002) has speculated that low resting heart rate may be related to aggressive and antisocial behavior through a tendency towards sensation seeking and/or a tendency towards fearlessness. Recently, Raine (2002) suggested that the relationship between low resting heart rate and antisocial behavior may be related to reduced functioning in the right hemisphere of the brain. This speculation is consistent with contemporary explanations of variability in heart rate function. These explanations describe heart rate, and other measures of cardiac activity, as a function of an integrated system with direct effects through the parasympathetic and sympathetic nervous systems and indirect effects from distinct anatomical structures in the brain, including the amygdala, prefrontal cortex, cingulate cortex, and hypothalamus.

Many of the anatomical structures implicated in the control of heart rate are also related to variation in violent and antisocial behavior. For example, reviews of brain imaging research and recent studies find violent offenders, and those prone to aggression, show global dysfunction in the prefrontal cortex and specific dysfunction in anatomical structures within the prefrontal cortex, including the orbitofrontal cortex and the dorsolateral prefrontal cortex.

To extend the literature on the relationship between resting heart rate and antisocial behavior, Armstrong and his colleagues are collecting data from student volunteers at Sam Houston State University. An initial look at the data found that low resting heart rate was related to elevated levels of serious and violent antisocial behavior. Further, this relationship was not mediated by variables playing a central role in criminological theory, including peer behavior, parental attachment, and self-control. These results will appear in a forthcoming issue of Criminal Justice and Behavior. Currently, Scott MacMillan and Armstrong are exploring the extent to which low resting heart rate interacts with different aspects of the environment, including family functioning, to predict antisocial behavior. In the near future Armstrong and colleagues will attempt to expand their data collection efforts to include inmates incarcerated in correctional facilities.